P. berghei was successfully transmitted to rats, mice, and hamsters, using liver from sporozoite-infected rats without concomitant blood infections. These infections were successful when the donor liver was transferred to recipients at 2.5-7, 21-28, or 36-41 h postinjection of sporozoites into donors. The infections were not due to other life cycle stages of the parasite. There were not infective circulating sporozoites or merozoites in the donors because subinoculations of blood from donors at the time of liver transfer were always negative. Latent sporozoites are rigorously excluded as the possible cause of infectivity in the recipients because donor liver was infective for hyperimmunized, sporozoite-immune mice. These infections were due to the immature exoerythrocytic schizonts (EES) in the donor liver. The method of preparation of the infected liver inoculum was critical for the establishment of infection in the recipients. The most successful method of liver preparation was mincing, while homogenization completely destroyed the infectivity of the liver inoculum. Using this method of transferring malaria infection, it is demonstrated that immunity to malaria in sporozoite-immune mice does not extend to EES.